“I can’t prove it. But his cutting her robe and bra off suggests she was bound at the time.”

“What makes you so sure she was bound behind her back instead of in front? I know that’s what Oscar told the police. Is that what you’re basing it on?”

Scarpetta held out her wrists, the left one on top of the right, as if they were bound by a single strap.

“I’m basing it on the pattern of the furrow on her wrists, where the groove was the deepest, where there was sparing, et cetera,” she said. “If she’d been bound in front, it’s likely the strap would have been inserted under this wrist”—she indicated her right one—“with the locking block a little to the right of her right wrist bone. If they’d been bound behind her back, the position would have been reversed.”

“The killer right-handed or left-handed, in your opinion?”

“Based on the direction he pulled the strap during tightening? Consistent with someone left-handed, assuming he was facing her when he bound her. For what it’s worth, Oscar’s dominant hand is his right one. And I probably shouldn’t tell you that.”

She and Marino put on fresh gloves, and she stepped inside the bathroom and lifted the vanity chair and set it in the middle of the floor. She measured the height of it from its turned-up metal foot to the black fabric seat, which had darker areas, stained areas, that added to her theory.

“Possibly residues of the lubricant,” she said. “Nobody noticed because it was never considered that she might have been sitting in this chair when she was garroted, in front of the mirror. Maybe some tissue and blood on the legs from her thrashing. Let me see.”

She looked with a magnification lens.

“I can’t tell. But maybe not. Not really surprised. Since her injuries are to the tops of her legs, not the backs of them. You still carry those little tactical lights that can blind people?”

Marino dug into his pocket and pulled out his flashlight and gave it to her. She got down on her knees and shone the light under the vanity, illuminating smears of dark dried blood under the counter’s edge, not visible unless one was on the floor, looking. She found more blood on the underside of the vanity drawer, which was unpainted plywood. Marino squatted, and she showed him.

She took photographs.

“I’m going to swab all this, but not the chair,” she said. “What we’re going to do is wrap it up, and it goes to La Guardia. Can you step out for a minute and tell Jaime we need an officer who can escort this chair to Lucy’s jet and be on that jet and receipt it to Dr. Kiselstein at the airport in Knoxville? Lucy can set it up. In fact, knowing her, she already has.”